摘要
根据1960～2008年近49年的邵阳县单站月降水资料，利用z指数旱涝指标，对邵阳县单站的年和各季节进行了旱涝分析，结果表明：z指数旱涝指标能较好地反映邵阳县近49年来的旱涝演变情况，邵阳县降水旱年有11年，出现频率为22．4％，涝年有14年，出现频率为28．6％，旱涝相间特征明显．年降水量呈上升趋势，增加速率为14．5mm／10a，向洪涝化趋势发展．四季的z指数变化趋势不同，冬、夏季的变化呈上升趋势，为洪涝增强趋势且明显；春、秋季是下降趋势即干旱增强趋势但不明显．近49年来邵阳县发生季节性旱涝频率较高，各季旱涝灾害具有频繁性、旱涝相间性及连续性．旱涝灾害是影响农作物的主要因素之一，分析结果对旱涝趋势预测和防灾减灾具有参考作用．
According to the monthly rainfall data from 1960 to 2008 in Shaoyang station, by using the Z index of drought index, annual and seasonal drought were analyzed in Shaoyang. It shows that Z index of drought index can reflect the drought and flood evolution in recent 49 years in Shaoyang County, it is drought for 11 years, the frequency is 22. 4%, and the flood years is 14, the frequency is 28.6% ,which has obvious characteristics of drought and flood changing. The annual precipitation is increasing, the increase rate was 14. 5mm/10a,which has a flood trendeney. The changing trendency of Z index is different in four seasons ,which is rising in winter and summer, and the flood increase obviously. It is falling in spring and autumn, and drought enhanced but the trend is not obviously. The frequency of seasonal drought and flood is higher in Shaoyang, which has obvious characteristics of drought and flood changing. The disaster is one of the main factors that affect crops, so the study can provide reference for drought and flood fore- casting and disaster prevention and reduction.
出处
《邵阳学院学报（自然科学版）》
2015年第3期42-47,共6页
Journal of Shaoyang University：Natural Science Edition
关键词
邵阳县
旱涝变化特征
Z指数
Shaoyang County
flood and drought change characteristics
Z index
